Why is my IF statement not working!?

[sam06]

Absolutely no idea why my IF statement's playing up - needs some fresh eyes I think!

 

if ($postcheck != $post){

if ($x == "0"){
	echo $title;
	echo "<br>";
	$x = "1";
	$y = $y + 1;
}
echo "Change Post to: ";
echo $postcheck;
echo " from ";
echo $post;
echo "<br>";

$result2 = mysql_query("UPDATE items SET Post='$postcheck' WHERE ID='$id'") 
or die(mysql_error()); 

}

 

When it returns $postcheck and $post, in this case, they're coming out as the same thing (on one record - no others!) - $post is retrieved from a database, and $postcheck is calculated. Both are numbers. Any ideas?!

[coupe-r]

Before your IF(), echo both vars on the screen so you can see what is being compared.

 

 

*** Nevermind, was looking at something else. 

[btherl]

Can you also tell us what you expected to see and what you actually saw.  I'm not clear on whether the "if" succeeded when you thought it wouldn't, or it failed when you thought it would succeed.

[sam06]

Running:

echo $postcheck;
echo "<br>";
echo $post;
echo "<br>";

before the if statement gives me:

1.89
1.89
Example Item 1
Change Post to: 1.89 from 1.89

 

The 1.89 and 1.89 look the same to me, so no idea why it's running the != statement...?!

 

Should expect no output

[coupe-r]

Can you show how you are getting those vars?

ie. $post = $row['post'];??

 

  Also, how are they stored in the DB? (datatype)

[Psycho]

I would also suggest changing those echo statements to something  like this

echo "Postcheck: [$postcheck]<br>";
echo "Post: [$post]<br>";

 

It could be something as simple as a leading/trailing space, which the brackets should make apparent. You should also view the HTML source code to see if there is anything different.

[btherl]

Looks like a trailing space will cause them to compare differently, but not a leading space:

 

<?
$a = '1.89';
$b = ' 1.89';
if ($a != $b) print "[$a] != [$b]\n";
$b = '1.89 ';
if ($a != $b) print "[$a] != [$b]\n";
?>

 

Print out urlencode($post) is also a good way of finding any hidden characters.

[sam06]

Just changed the datatype in the DB to decimal.

Now is throwing up the same error in another record!

 

Using the brackets echo from above I now get:

 

Postcheck: [1.99]
Post: [1.99]

Postcheck: [1.19]
Post: [1.19]
Example Item 2
Change Post to: 1.19 from 1.19

Postcheck: [1.49]
Post: [1.49]

[btherl]

Well that is odd indeed.  Can you try printing the values like this:

 

echo "Postcheck: [" . urlencode($postcheck) . "]<br>";
echo "Post: [" . urlencode($post) . "]<br>";

 

If that shows them to be identical, try this:

 

echo "<pre>";
echo "Postcheck: "; var_dump($postcheck);
echo "Post: "; var_dump($post);

 

One of those should show up why they look the same but are unequal according to php.

[sam06]

I've changed it to reverse - if theyre the same, do nothing, else this - and that works!

 

It returns:

 

float 1.99

 

Post:

 

string '1.99' (length=4)

 

 

Postcheck:

 

float 1.19

 

Post:

 

string '1.19' (length=4)

 

 

Postcheck:

 

float 1.49

 

Post:

 

string '1.49' (length=4)